APPLICATION PROGRAMMING INTERFACE

The cloning character-special device /dev/spwr is used to access all SMC EtherPower
II devices installed within the system.

The spwr driver is dependent on /kernel/misc/gld, a loadable
kernel module that provides the spwr driver with the DLPI and
STREAMS functionality required of a LAN driver. See gld(7D)
for more details on the primitives supported by the driver.

The values returned by the driver in the DL_INFO_ACK primitive in
response to the DL_INFO_REQ from the user are as follows:

The maximum SDU is 1500 ( ETHERMTU).

The minimum SDU is 0. The spwr driver will pad to the mandatory 60-octet minimum packet size.

The DLSAP address length is 8.

The MAC type is DL_ETHER.

The SAP length value is –2, meaning the physical address component is followed immediately by a 2-byte SAP component within the DLSAP address.